CRP and IL-6 levels are elevated in patients presenting in AFL. Given the lower CS values in these patients, their origin appears to be systemic rather than cardiac. Because these levels significantly fall after ablation of AFL, the atrial tachyarrhythmia appears to be the cause (not the effect) of the inflammation.

No abstract

No abstract

No abstract

An efficient protocol was developed to obtain homopropargylic alcohols. Subjecting alkynyllithiums and ethylene oxide to 10-20 mol% of trimethylaluminum provided homopropargylic alcohols in good yields.Successful completion of a synthesis of a natural product possessing moderate complexity typically requires the preparation of starting materials in gram quantities. The syntheses of these relatively simple and low molecular weight precursors are usually the least interesting in a synthetic sequence that may ultimately lead to an interesting bioactive compound via a novel carbon-carbon bond forming reaction. However, low yields in the beginning stages of a synthesis can foil the best of synthetic strategies if key step precursors cannot be accessed in sufficient quantities.Recently, while working towards the synthesis of guanacastepene A, we desired the homopropargylic alcohol 3 in gram quantities. We obtained this alcohol by addition of ethylene oxide (2) to lithiated 3-methyl-1-butyne (1); 1 however, the yields of this reaction suddenly went from 95% to 10%. After some experimentation, the irreproducibility of this reaction was traced to the ethylene oxide. It was observed that an older expired lecture bottle of ethylene oxide gave 95% yields of alkynol 3. Since the older bottle had been discarded, we could only speculate that a contaminant was responsible for the higher yields. Based upon our need for a reliable and cheap protocol for the preparation of gram quantities of homopropargylic alcohol 3, we initiated a systematic investigation into the addition reaction of acetylides to ethylene oxide (Equation 1). Equation 1There are many reports of Lewis acids catalyzing the addition of acetylides to epoxides, the most common of which was developed by Yamaguchi and Hirao 2 using a stoichiometric amount of boron trifluoride etherate. In our hands this protocol was not only technically challenging upon scale up, but inseparable by-products were formed. Another reagent used to facilitate the reaction between epoxides and alkynyllithiums is catalytic amounts of trimethylgallium. 3 This methodology appears to be a very efficient way to form homopropargylic alcohols; however, it seems not to be a very well-liked protocol. It is thought that the cost ($13 per gram) of Me 3 Ga and special handling needs detract from its usefulness.Stoichiometric amounts of trimethylaluminium (TMA) have been reported to promote reaction with epoxides to give good to moderate yields; however, in some cases TMA was not reactive enough and needed to be used in conjunction with stoichiometric amounts of BF 3 ·OEt 2 . 4 In one publication, catalytic TMA could be used only if the acetylide was reacted with an epoxy ether, not a simple epoxide like 5-phenyl-1-pentene oxide. 5 There were also reports of the use of diethylaluminum chloride by Fried, 6 which gave good yields for the addition of the alkynyllithium of octyne, but low yields for more complex alkynes. Herein, we report the use of catalytic TMA for the formation of a variety of homoproparg...